In other studies of KRASmut lung cancer, anti-PD-1 combined with inhibition of the AKT-mTOR pathway by mTOR inhibitor or the STAT3 pathway by natural compound luteolin can remarkably decreased the expression of PD-1 or PD-L1, respectively, which consequently surmounts the resistance to anti-PD-1[127,128]. This evidence concerns the gene PDCD1 and lung cancer.